xref: /openbmc/linux/drivers/mfd/twl4030-irq.c (revision ecefa105)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * twl4030-irq.c - TWL4030/TPS659x0 irq support
4  *
5  * Copyright (C) 2005-2006 Texas Instruments, Inc.
6  *
7  * Modifications to defer interrupt handling to a kernel thread:
8  * Copyright (C) 2006 MontaVista Software, Inc.
9  *
10  * Based on tlv320aic23.c:
11  * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
12  *
13  * Code cleanup and modifications to IRQ handler.
14  * by syed khasim <x0khasim@ti.com>
15  */
16 
17 #include <linux/device.h>
18 #include <linux/export.h>
19 #include <linux/interrupt.h>
20 #include <linux/irq.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/irqdomain.h>
24 #include <linux/mfd/twl.h>
25 
26 #include "twl-core.h"
27 
28 /*
29  * TWL4030 IRQ handling has two stages in hardware, and thus in software.
30  * The Primary Interrupt Handler (PIH) stage exposes status bits saying
31  * which Secondary Interrupt Handler (SIH) stage is raising an interrupt.
32  * SIH modules are more traditional IRQ components, which support per-IRQ
33  * enable/disable and trigger controls; they do most of the work.
34  *
35  * These chips are designed to support IRQ handling from two different
36  * I2C masters.  Each has a dedicated IRQ line, and dedicated IRQ status
37  * and mask registers in the PIH and SIH modules.
38  *
39  * We set up IRQs starting at a platform-specified base, always starting
40  * with PIH and the SIH for PWR_INT and then usually adding GPIO:
41  *	base + 0  .. base + 7	PIH
42  *	base + 8  .. base + 15	SIH for PWR_INT
43  *	base + 16 .. base + 33	SIH for GPIO
44  */
45 #define TWL4030_CORE_NR_IRQS	8
46 #define TWL4030_PWR_NR_IRQS	8
47 
48 /* PIH register offsets */
49 #define REG_PIH_ISR_P1			0x01
50 #define REG_PIH_ISR_P2			0x02
51 #define REG_PIH_SIR			0x03	/* for testing */
52 
53 /* Linux could (eventually) use either IRQ line */
54 static int irq_line;
55 
56 struct sih {
57 	char	name[8];
58 	u8	module;			/* module id */
59 	u8	control_offset;		/* for SIH_CTRL */
60 	bool	set_cor;
61 
62 	u8	bits;			/* valid in isr/imr */
63 	u8	bytes_ixr;		/* bytelen of ISR/IMR/SIR */
64 
65 	u8	edr_offset;
66 	u8	bytes_edr;		/* bytelen of EDR */
67 
68 	u8	irq_lines;		/* number of supported irq lines */
69 
70 	/* SIR ignored -- set interrupt, for testing only */
71 	struct sih_irq_data {
72 		u8	isr_offset;
73 		u8	imr_offset;
74 	} mask[2];
75 	/* + 2 bytes padding */
76 };
77 
78 static const struct sih *sih_modules;
79 static int nr_sih_modules;
80 
81 #define SIH_INITIALIZER(modname, nbits) \
82 	.module		= TWL4030_MODULE_ ## modname, \
83 	.control_offset = TWL4030_ ## modname ## _SIH_CTRL, \
84 	.bits		= nbits, \
85 	.bytes_ixr	= DIV_ROUND_UP(nbits, 8), \
86 	.edr_offset	= TWL4030_ ## modname ## _EDR, \
87 	.bytes_edr	= DIV_ROUND_UP((2*(nbits)), 8), \
88 	.irq_lines	= 2, \
89 	.mask = { { \
90 		.isr_offset	= TWL4030_ ## modname ## _ISR1, \
91 		.imr_offset	= TWL4030_ ## modname ## _IMR1, \
92 	}, \
93 	{ \
94 		.isr_offset	= TWL4030_ ## modname ## _ISR2, \
95 		.imr_offset	= TWL4030_ ## modname ## _IMR2, \
96 	}, },
97 
98 /* register naming policies are inconsistent ... */
99 #define TWL4030_INT_PWR_EDR		TWL4030_INT_PWR_EDR1
100 #define TWL4030_MODULE_KEYPAD_KEYP	TWL4030_MODULE_KEYPAD
101 #define TWL4030_MODULE_INT_PWR		TWL4030_MODULE_INT
102 
103 
104 /*
105  * Order in this table matches order in PIH_ISR.  That is,
106  * BIT(n) in PIH_ISR is sih_modules[n].
107  */
108 /* sih_modules_twl4030 is used both in twl4030 and twl5030 */
109 static const struct sih sih_modules_twl4030[6] = {
110 	[0] = {
111 		.name		= "gpio",
112 		.module		= TWL4030_MODULE_GPIO,
113 		.control_offset	= REG_GPIO_SIH_CTRL,
114 		.set_cor	= true,
115 		.bits		= TWL4030_GPIO_MAX,
116 		.bytes_ixr	= 3,
117 		/* Note: *all* of these IRQs default to no-trigger */
118 		.edr_offset	= REG_GPIO_EDR1,
119 		.bytes_edr	= 5,
120 		.irq_lines	= 2,
121 		.mask = { {
122 			.isr_offset	= REG_GPIO_ISR1A,
123 			.imr_offset	= REG_GPIO_IMR1A,
124 		}, {
125 			.isr_offset	= REG_GPIO_ISR1B,
126 			.imr_offset	= REG_GPIO_IMR1B,
127 		}, },
128 	},
129 	[1] = {
130 		.name		= "keypad",
131 		.set_cor	= true,
132 		SIH_INITIALIZER(KEYPAD_KEYP, 4)
133 	},
134 	[2] = {
135 		.name		= "bci",
136 		.module		= TWL4030_MODULE_INTERRUPTS,
137 		.control_offset	= TWL4030_INTERRUPTS_BCISIHCTRL,
138 		.set_cor	= true,
139 		.bits		= 12,
140 		.bytes_ixr	= 2,
141 		.edr_offset	= TWL4030_INTERRUPTS_BCIEDR1,
142 		/* Note: most of these IRQs default to no-trigger */
143 		.bytes_edr	= 3,
144 		.irq_lines	= 2,
145 		.mask = { {
146 			.isr_offset	= TWL4030_INTERRUPTS_BCIISR1A,
147 			.imr_offset	= TWL4030_INTERRUPTS_BCIIMR1A,
148 		}, {
149 			.isr_offset	= TWL4030_INTERRUPTS_BCIISR1B,
150 			.imr_offset	= TWL4030_INTERRUPTS_BCIIMR1B,
151 		}, },
152 	},
153 	[3] = {
154 		.name		= "madc",
155 		SIH_INITIALIZER(MADC, 4)
156 	},
157 	[4] = {
158 		/* USB doesn't use the same SIH organization */
159 		.name		= "usb",
160 	},
161 	[5] = {
162 		.name		= "power",
163 		.set_cor	= true,
164 		SIH_INITIALIZER(INT_PWR, 8)
165 	},
166 		/* there are no SIH modules #6 or #7 ... */
167 };
168 
169 static const struct sih sih_modules_twl5031[8] = {
170 	[0] = {
171 		.name		= "gpio",
172 		.module		= TWL4030_MODULE_GPIO,
173 		.control_offset	= REG_GPIO_SIH_CTRL,
174 		.set_cor	= true,
175 		.bits		= TWL4030_GPIO_MAX,
176 		.bytes_ixr	= 3,
177 		/* Note: *all* of these IRQs default to no-trigger */
178 		.edr_offset	= REG_GPIO_EDR1,
179 		.bytes_edr	= 5,
180 		.irq_lines	= 2,
181 		.mask = { {
182 			.isr_offset	= REG_GPIO_ISR1A,
183 			.imr_offset	= REG_GPIO_IMR1A,
184 		}, {
185 			.isr_offset	= REG_GPIO_ISR1B,
186 			.imr_offset	= REG_GPIO_IMR1B,
187 		}, },
188 	},
189 	[1] = {
190 		.name		= "keypad",
191 		.set_cor	= true,
192 		SIH_INITIALIZER(KEYPAD_KEYP, 4)
193 	},
194 	[2] = {
195 		.name		= "bci",
196 		.module		= TWL5031_MODULE_INTERRUPTS,
197 		.control_offset	= TWL5031_INTERRUPTS_BCISIHCTRL,
198 		.bits		= 7,
199 		.bytes_ixr	= 1,
200 		.edr_offset	= TWL5031_INTERRUPTS_BCIEDR1,
201 		/* Note: most of these IRQs default to no-trigger */
202 		.bytes_edr	= 2,
203 		.irq_lines	= 2,
204 		.mask = { {
205 			.isr_offset	= TWL5031_INTERRUPTS_BCIISR1,
206 			.imr_offset	= TWL5031_INTERRUPTS_BCIIMR1,
207 		}, {
208 			.isr_offset	= TWL5031_INTERRUPTS_BCIISR2,
209 			.imr_offset	= TWL5031_INTERRUPTS_BCIIMR2,
210 		}, },
211 	},
212 	[3] = {
213 		.name		= "madc",
214 		SIH_INITIALIZER(MADC, 4)
215 	},
216 	[4] = {
217 		/* USB doesn't use the same SIH organization */
218 		.name		= "usb",
219 	},
220 	[5] = {
221 		.name		= "power",
222 		.set_cor	= true,
223 		SIH_INITIALIZER(INT_PWR, 8)
224 	},
225 	[6] = {
226 		/*
227 		 * ECI/DBI doesn't use the same SIH organization.
228 		 * For example, it supports only one interrupt output line.
229 		 * That is, the interrupts are seen on both INT1 and INT2 lines.
230 		 */
231 		.name		= "eci_dbi",
232 		.module		= TWL5031_MODULE_ACCESSORY,
233 		.bits		= 9,
234 		.bytes_ixr	= 2,
235 		.irq_lines	= 1,
236 		.mask = { {
237 			.isr_offset	= TWL5031_ACIIDR_LSB,
238 			.imr_offset	= TWL5031_ACIIMR_LSB,
239 		}, },
240 
241 	},
242 	[7] = {
243 		/* Audio accessory */
244 		.name		= "audio",
245 		.module		= TWL5031_MODULE_ACCESSORY,
246 		.control_offset	= TWL5031_ACCSIHCTRL,
247 		.bits		= 2,
248 		.bytes_ixr	= 1,
249 		.edr_offset	= TWL5031_ACCEDR1,
250 		/* Note: most of these IRQs default to no-trigger */
251 		.bytes_edr	= 1,
252 		.irq_lines	= 2,
253 		.mask = { {
254 			.isr_offset	= TWL5031_ACCISR1,
255 			.imr_offset	= TWL5031_ACCIMR1,
256 		}, {
257 			.isr_offset	= TWL5031_ACCISR2,
258 			.imr_offset	= TWL5031_ACCIMR2,
259 		}, },
260 	},
261 };
262 
263 #undef TWL4030_MODULE_KEYPAD_KEYP
264 #undef TWL4030_MODULE_INT_PWR
265 #undef TWL4030_INT_PWR_EDR
266 
267 /*----------------------------------------------------------------------*/
268 
269 static unsigned twl4030_irq_base;
270 
271 /*
272  * handle_twl4030_pih() is the desc->handle method for the twl4030 interrupt.
273  * This is a chained interrupt, so there is no desc->action method for it.
274  * Now we need to query the interrupt controller in the twl4030 to determine
275  * which module is generating the interrupt request.  However, we can't do i2c
276  * transactions in interrupt context, so we must defer that work to a kernel
277  * thread.  All we do here is acknowledge and mask the interrupt and wakeup
278  * the kernel thread.
279  */
280 static irqreturn_t handle_twl4030_pih(int irq, void *devid)
281 {
282 	irqreturn_t	ret;
283 	u8		pih_isr;
284 
285 	ret = twl_i2c_read_u8(TWL_MODULE_PIH, &pih_isr,
286 			      REG_PIH_ISR_P1);
287 	if (ret) {
288 		pr_warn("twl4030: I2C error %d reading PIH ISR\n", ret);
289 		return IRQ_NONE;
290 	}
291 
292 	while (pih_isr) {
293 		unsigned long	pending = __ffs(pih_isr);
294 		unsigned int	irq;
295 
296 		pih_isr &= ~BIT(pending);
297 		irq = pending + twl4030_irq_base;
298 		handle_nested_irq(irq);
299 	}
300 
301 	return IRQ_HANDLED;
302 }
303 
304 /*----------------------------------------------------------------------*/
305 
306 /*
307  * twl4030_init_sih_modules() ... start from a known state where no
308  * IRQs will be coming in, and where we can quickly enable them then
309  * handle them as they arrive.  Mask all IRQs: maybe init SIH_CTRL.
310  *
311  * NOTE:  we don't touch EDR registers here; they stay with hardware
312  * defaults or whatever the last value was.  Note that when both EDR
313  * bits for an IRQ are clear, that's as if its IMR bit is set...
314  */
315 static int twl4030_init_sih_modules(unsigned line)
316 {
317 	const struct sih *sih;
318 	u8 buf[4];
319 	int i;
320 	int status;
321 
322 	/* line 0 == int1_n signal; line 1 == int2_n signal */
323 	if (line > 1)
324 		return -EINVAL;
325 
326 	irq_line = line;
327 
328 	/* disable all interrupts on our line */
329 	memset(buf, 0xff, sizeof(buf));
330 	sih = sih_modules;
331 	for (i = 0; i < nr_sih_modules; i++, sih++) {
332 		/* skip USB -- it's funky */
333 		if (!sih->bytes_ixr)
334 			continue;
335 
336 		/* Not all the SIH modules support multiple interrupt lines */
337 		if (sih->irq_lines <= line)
338 			continue;
339 
340 		status = twl_i2c_write(sih->module, buf,
341 				sih->mask[line].imr_offset, sih->bytes_ixr);
342 		if (status < 0)
343 			pr_err("twl4030: err %d initializing %s %s\n",
344 					status, sih->name, "IMR");
345 
346 		/*
347 		 * Maybe disable "exclusive" mode; buffer second pending irq;
348 		 * set Clear-On-Read (COR) bit.
349 		 *
350 		 * NOTE that sometimes COR polarity is documented as being
351 		 * inverted:  for MADC, COR=1 means "clear on write".
352 		 * And for PWR_INT it's not documented...
353 		 */
354 		if (sih->set_cor) {
355 			status = twl_i2c_write_u8(sih->module,
356 					TWL4030_SIH_CTRL_COR_MASK,
357 					sih->control_offset);
358 			if (status < 0)
359 				pr_err("twl4030: err %d initializing %s %s\n",
360 						status, sih->name, "SIH_CTRL");
361 		}
362 	}
363 
364 	sih = sih_modules;
365 	for (i = 0; i < nr_sih_modules; i++, sih++) {
366 		u8 rxbuf[4];
367 		int j;
368 
369 		/* skip USB */
370 		if (!sih->bytes_ixr)
371 			continue;
372 
373 		/* Not all the SIH modules support multiple interrupt lines */
374 		if (sih->irq_lines <= line)
375 			continue;
376 
377 		/*
378 		 * Clear pending interrupt status.  Either the read was
379 		 * enough, or we need to write those bits.  Repeat, in
380 		 * case an IRQ is pending (PENDDIS=0) ... that's not
381 		 * uncommon with PWR_INT.PWRON.
382 		 */
383 		for (j = 0; j < 2; j++) {
384 			status = twl_i2c_read(sih->module, rxbuf,
385 				sih->mask[line].isr_offset, sih->bytes_ixr);
386 			if (status < 0)
387 				pr_warn("twl4030: err %d initializing %s %s\n",
388 					status, sih->name, "ISR");
389 
390 			if (!sih->set_cor) {
391 				status = twl_i2c_write(sih->module, buf,
392 					sih->mask[line].isr_offset,
393 					sih->bytes_ixr);
394 				if (status < 0)
395 					pr_warn("twl4030: write failed: %d\n",
396 						status);
397 			}
398 			/*
399 			 * else COR=1 means read sufficed.
400 			 * (for most SIH modules...)
401 			 */
402 		}
403 	}
404 
405 	return 0;
406 }
407 
408 static inline void activate_irq(int irq)
409 {
410 	irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);
411 }
412 
413 /*----------------------------------------------------------------------*/
414 
415 struct sih_agent {
416 	int			irq_base;
417 	const struct sih	*sih;
418 
419 	u32			imr;
420 	bool			imr_change_pending;
421 
422 	u32			edge_change;
423 
424 	struct mutex		irq_lock;
425 	char			*irq_name;
426 };
427 
428 /*----------------------------------------------------------------------*/
429 
430 /*
431  * All irq_chip methods get issued from code holding irq_desc[irq].lock,
432  * which can't perform the underlying I2C operations (because they sleep).
433  * So we must hand them off to a thread (workqueue) and cope with asynch
434  * completion, potentially including some re-ordering, of these requests.
435  */
436 
437 static void twl4030_sih_mask(struct irq_data *data)
438 {
439 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
440 
441 	agent->imr |= BIT(data->irq - agent->irq_base);
442 	agent->imr_change_pending = true;
443 }
444 
445 static void twl4030_sih_unmask(struct irq_data *data)
446 {
447 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
448 
449 	agent->imr &= ~BIT(data->irq - agent->irq_base);
450 	agent->imr_change_pending = true;
451 }
452 
453 static int twl4030_sih_set_type(struct irq_data *data, unsigned trigger)
454 {
455 	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
456 
457 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
458 		return -EINVAL;
459 
460 	if (irqd_get_trigger_type(data) != trigger)
461 		agent->edge_change |= BIT(data->irq - agent->irq_base);
462 
463 	return 0;
464 }
465 
466 static void twl4030_sih_bus_lock(struct irq_data *data)
467 {
468 	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
469 
470 	mutex_lock(&agent->irq_lock);
471 }
472 
473 static void twl4030_sih_bus_sync_unlock(struct irq_data *data)
474 {
475 	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
476 	const struct sih	*sih = agent->sih;
477 	int			status;
478 
479 	if (agent->imr_change_pending) {
480 		union {
481 			__le32	word;
482 			u8	bytes[4];
483 		} imr;
484 
485 		/* byte[0] gets overwritten as we write ... */
486 		imr.word = cpu_to_le32(agent->imr);
487 		agent->imr_change_pending = false;
488 
489 		/* write the whole mask ... simpler than subsetting it */
490 		status = twl_i2c_write(sih->module, imr.bytes,
491 				sih->mask[irq_line].imr_offset,
492 				sih->bytes_ixr);
493 		if (status)
494 			pr_err("twl4030: %s, %s --> %d\n", __func__,
495 					"write", status);
496 	}
497 
498 	if (agent->edge_change) {
499 		u32		edge_change;
500 		u8		bytes[6];
501 
502 		edge_change = agent->edge_change;
503 		agent->edge_change = 0;
504 
505 		/*
506 		 * Read, reserving first byte for write scratch.  Yes, this
507 		 * could be cached for some speedup ... but be careful about
508 		 * any processor on the other IRQ line, EDR registers are
509 		 * shared.
510 		 */
511 		status = twl_i2c_read(sih->module, bytes,
512 				sih->edr_offset, sih->bytes_edr);
513 		if (status) {
514 			pr_err("twl4030: %s, %s --> %d\n", __func__,
515 					"read", status);
516 			return;
517 		}
518 
519 		/* Modify only the bits we know must change */
520 		while (edge_change) {
521 			int		i = fls(edge_change) - 1;
522 			int		byte = i >> 2;
523 			int		off = (i & 0x3) * 2;
524 			unsigned int	type;
525 
526 			bytes[byte] &= ~(0x03 << off);
527 
528 			type = irq_get_trigger_type(i + agent->irq_base);
529 			if (type & IRQ_TYPE_EDGE_RISING)
530 				bytes[byte] |= BIT(off + 1);
531 			if (type & IRQ_TYPE_EDGE_FALLING)
532 				bytes[byte] |= BIT(off + 0);
533 
534 			edge_change &= ~BIT(i);
535 		}
536 
537 		/* Write */
538 		status = twl_i2c_write(sih->module, bytes,
539 				sih->edr_offset, sih->bytes_edr);
540 		if (status)
541 			pr_err("twl4030: %s, %s --> %d\n", __func__,
542 					"write", status);
543 	}
544 
545 	mutex_unlock(&agent->irq_lock);
546 }
547 
548 static struct irq_chip twl4030_sih_irq_chip = {
549 	.name		= "twl4030",
550 	.irq_mask	= twl4030_sih_mask,
551 	.irq_unmask	= twl4030_sih_unmask,
552 	.irq_set_type	= twl4030_sih_set_type,
553 	.irq_bus_lock	= twl4030_sih_bus_lock,
554 	.irq_bus_sync_unlock = twl4030_sih_bus_sync_unlock,
555 	.flags		= IRQCHIP_SKIP_SET_WAKE,
556 };
557 
558 /*----------------------------------------------------------------------*/
559 
560 static inline int sih_read_isr(const struct sih *sih)
561 {
562 	int status;
563 	union {
564 		u8 bytes[4];
565 		__le32 word;
566 	} isr;
567 
568 	/* FIXME need retry-on-error ... */
569 
570 	isr.word = 0;
571 	status = twl_i2c_read(sih->module, isr.bytes,
572 			sih->mask[irq_line].isr_offset, sih->bytes_ixr);
573 
574 	return (status < 0) ? status : le32_to_cpu(isr.word);
575 }
576 
577 /*
578  * Generic handler for SIH interrupts ... we "know" this is called
579  * in task context, with IRQs enabled.
580  */
581 static irqreturn_t handle_twl4030_sih(int irq, void *data)
582 {
583 	struct sih_agent *agent = irq_get_handler_data(irq);
584 	const struct sih *sih = agent->sih;
585 	int isr;
586 
587 	/* reading ISR acks the IRQs, using clear-on-read mode */
588 	isr = sih_read_isr(sih);
589 
590 	if (isr < 0) {
591 		pr_err("twl4030: %s SIH, read ISR error %d\n",
592 			sih->name, isr);
593 		/* REVISIT:  recover; eventually mask it all, etc */
594 		return IRQ_HANDLED;
595 	}
596 
597 	while (isr) {
598 		irq = fls(isr);
599 		irq--;
600 		isr &= ~BIT(irq);
601 
602 		if (irq < sih->bits)
603 			handle_nested_irq(agent->irq_base + irq);
604 		else
605 			pr_err("twl4030: %s SIH, invalid ISR bit %d\n",
606 				sih->name, irq);
607 	}
608 	return IRQ_HANDLED;
609 }
610 
611 /* returns the first IRQ used by this SIH bank, or negative errno */
612 int twl4030_sih_setup(struct device *dev, int module, int irq_base)
613 {
614 	int			sih_mod;
615 	const struct sih	*sih = NULL;
616 	struct sih_agent	*agent;
617 	int			i, irq;
618 	int			status = -EINVAL;
619 
620 	/* only support modules with standard clear-on-read for now */
621 	for (sih_mod = 0, sih = sih_modules; sih_mod < nr_sih_modules;
622 			sih_mod++, sih++) {
623 		if (sih->module == module && sih->set_cor) {
624 			status = 0;
625 			break;
626 		}
627 	}
628 
629 	if (status < 0) {
630 		dev_err(dev, "module to setup SIH for not found\n");
631 		return status;
632 	}
633 
634 	agent = kzalloc(sizeof(*agent), GFP_KERNEL);
635 	if (!agent)
636 		return -ENOMEM;
637 
638 	agent->irq_base = irq_base;
639 	agent->sih = sih;
640 	agent->imr = ~0;
641 	mutex_init(&agent->irq_lock);
642 
643 	for (i = 0; i < sih->bits; i++) {
644 		irq = irq_base + i;
645 
646 		irq_set_chip_data(irq, agent);
647 		irq_set_chip_and_handler(irq, &twl4030_sih_irq_chip,
648 					 handle_edge_irq);
649 		irq_set_nested_thread(irq, 1);
650 		activate_irq(irq);
651 	}
652 
653 	/* replace generic PIH handler (handle_simple_irq) */
654 	irq = sih_mod + twl4030_irq_base;
655 	irq_set_handler_data(irq, agent);
656 	agent->irq_name = kasprintf(GFP_KERNEL, "twl4030_%s", sih->name);
657 	status = request_threaded_irq(irq, NULL, handle_twl4030_sih,
658 				      IRQF_EARLY_RESUME | IRQF_ONESHOT,
659 				      agent->irq_name ?: sih->name, NULL);
660 
661 	dev_info(dev, "%s (irq %d) chaining IRQs %d..%d\n", sih->name,
662 			irq, irq_base, irq_base + i - 1);
663 
664 	return status < 0 ? status : irq_base;
665 }
666 
667 /* FIXME need a call to reverse twl4030_sih_setup() ... */
668 
669 /*----------------------------------------------------------------------*/
670 
671 /* FIXME pass in which interrupt line we'll use ... */
672 #define twl_irq_line	0
673 
674 int twl4030_init_irq(struct device *dev, int irq_num)
675 {
676 	static struct irq_chip	twl4030_irq_chip;
677 	int			status, i;
678 	int			irq_base, irq_end, nr_irqs;
679 	struct			device_node *node = dev->of_node;
680 
681 	/*
682 	 * TWL core and pwr interrupts must be contiguous because
683 	 * the hwirqs numbers are defined contiguously from 1 to 15.
684 	 * Create only one domain for both.
685 	 */
686 	nr_irqs = TWL4030_PWR_NR_IRQS + TWL4030_CORE_NR_IRQS;
687 
688 	irq_base = irq_alloc_descs(-1, 0, nr_irqs, 0);
689 	if (irq_base < 0) {
690 		dev_err(dev, "Fail to allocate IRQ descs\n");
691 		return irq_base;
692 	}
693 
694 	irq_domain_add_legacy(node, nr_irqs, irq_base, 0,
695 			      &irq_domain_simple_ops, NULL);
696 
697 	irq_end = irq_base + TWL4030_CORE_NR_IRQS;
698 
699 	/*
700 	 * Mask and clear all TWL4030 interrupts since initially we do
701 	 * not have any TWL4030 module interrupt handlers present
702 	 */
703 	status = twl4030_init_sih_modules(twl_irq_line);
704 	if (status < 0)
705 		return status;
706 
707 	twl4030_irq_base = irq_base;
708 
709 	/*
710 	 * Install an irq handler for each of the SIH modules;
711 	 * clone dummy irq_chip since PIH can't *do* anything
712 	 */
713 	twl4030_irq_chip = dummy_irq_chip;
714 	twl4030_irq_chip.name = "twl4030";
715 
716 	twl4030_sih_irq_chip.irq_ack = dummy_irq_chip.irq_ack;
717 
718 	for (i = irq_base; i < irq_end; i++) {
719 		irq_set_chip_and_handler(i, &twl4030_irq_chip,
720 					 handle_simple_irq);
721 		irq_set_nested_thread(i, 1);
722 		activate_irq(i);
723 	}
724 
725 	dev_info(dev, "%s (irq %d) chaining IRQs %d..%d\n", "PIH",
726 			irq_num, irq_base, irq_end);
727 
728 	/* ... and the PWR_INT module ... */
729 	status = twl4030_sih_setup(dev, TWL4030_MODULE_INT, irq_end);
730 	if (status < 0) {
731 		dev_err(dev, "sih_setup PWR INT --> %d\n", status);
732 		goto fail;
733 	}
734 
735 	/* install an irq handler to demultiplex the TWL4030 interrupt */
736 	status = request_threaded_irq(irq_num, NULL, handle_twl4030_pih,
737 				      IRQF_ONESHOT,
738 				      "TWL4030-PIH", NULL);
739 	if (status < 0) {
740 		dev_err(dev, "could not claim irq%d: %d\n", irq_num, status);
741 		goto fail_rqirq;
742 	}
743 	enable_irq_wake(irq_num);
744 
745 	return irq_base;
746 fail_rqirq:
747 	/* clean up twl4030_sih_setup */
748 fail:
749 	for (i = irq_base; i < irq_end; i++) {
750 		irq_set_nested_thread(i, 0);
751 		irq_set_chip_and_handler(i, NULL, NULL);
752 	}
753 
754 	return status;
755 }
756 
757 void twl4030_exit_irq(void)
758 {
759 	/* FIXME undo twl_init_irq() */
760 	if (twl4030_irq_base)
761 		pr_err("twl4030: can't yet clean up IRQs?\n");
762 }
763 
764 int twl4030_init_chip_irq(const char *chip)
765 {
766 	if (!strcmp(chip, "twl5031")) {
767 		sih_modules = sih_modules_twl5031;
768 		nr_sih_modules = ARRAY_SIZE(sih_modules_twl5031);
769 	} else {
770 		sih_modules = sih_modules_twl4030;
771 		nr_sih_modules = ARRAY_SIZE(sih_modules_twl4030);
772 	}
773 
774 	return 0;
775 }
776